Adjustable X-ray apparatus



May 23, 1950 Filed May 29, 1948 zz12RHIllllllllllllllllllllllllll!"IllllllllllfllIIIIIIIIIIIIIIIIJIII C.P. DAVIS, JR, ET AL ADJUSTABLE X-RAY APPARATUS 4 Shets-Sheet 1 INVENTORSR! WAGNER, Ew VAUGHN BY ATTORN EY y 1950 c. P. DAVIS, JR., ET AL2,508,449

ADJUSTABLE X-RAY APPARATUS flf-A v 147 $27 95 I 82 146 95 .74 6 55 lllr143 WM 31 75 VX1 ATTORNEY May 23, 1950 c. P. DAVIS, JR, ET AL ADJUSTABLEX-RAY APPARATUS 4 Sheets-Sheet 4 INVENTORS CYP DA v/sfQL. GUENTNEQ 12WAGNER, EW VAUGHN W Mm ATTORNEY Patented May 23, 1950 ADJUSTABLE X-RAYAPPARATUS Charles P. Davis, Jr., Robert L. Guentner, Robert J. Wagner,and Everett W. Vaughn, Baltimore, Md., assignors to WestinghouseElectric Corporation, East Pittsburgh, Pa., a corporation ofPennsylvania Application May 29, 1948, Serial No. 30,096

Claims. 1

This invention relates to X-ray apparatus and, more particularly, to anadjustable table with facilities for vertical and horizontalfiuoroscopy, as well as vertical and horizontal radiography.

The principal object of our invention, generally considered, is toprovide an apparatus for use in vertical and horizontal fluoroscopy inaddition to vertical and horizontal radiography, without requiring theinterchanging of the relative positions of the X-ray tube andfluoroscopic screen with respect to the patient-supporting table.

Another object of our invention is to provide a single tube X-ray tablewith two operating surfaces, one for fluoroscopy with the patientbetween the surface and the fluorescent screen, and one for radiographywith the patient between the surface and the tube head, with a film in acassette associated with a Bucky diaphragm inside of the table.

A further object of our invention is to provide an adjustable X-raytable of the handrocked type, counterbalanced for ease of operatlon for180 range from horizontal through vertical to the opposite horizontalposition, whereby it is unnecessary to use more than one X-ray tube andone fluorescent screen, and the relative positions of these parts neednot be shifted.

A still further object of our invention is to provide an adjustableX-ray table having a counterbalanced longitudinal carriage carrying across-carriage on which the screen and tube are mounted, said tablebeing reversible through 180 to make it unnecessary to shift therelative positions of the screen and tube, a latch being provided forholding the table in adjusted position, a self-locking crank beingprovided for moving the Bucky diaphragm, and the screen being providedwith a three-position device useable to let the screen operate freelyfor vertical fiuoroscopy, to have the screen balanced for use inhorizontal fluoroscopy, or with the screen locked to prevent dropping onthe floor for use in horizontal radiography.

Other objects and advantages of the invention, relating to theparticular arrangement and construction of the various parts, willbecome apparent as the description proceeds.

Referring to the drawing:

Figure l is a side elevational view of our table adjusted for horizontalradiography.

Figure 2 is a side elevational view of our table adjusted for verticalradiography.

Figure 3 is a side elevational view of our table adjusted for horizontalfluoroscopy.

Figure 4 is a side elevational view of our table adjusted for verticalmicroscopy.

Figure 5 is an end elevational view of the table as illustrated inFigure 3.

Figure 6 is an end elevational view of the table as illustrated inFigure 1.

Figure '7 is an enlarged fragmentary side elevational view of the tablein the position of Figure l, with parts in vertical section on the lineVII-VII of Figure 10, in the direction of the arrows.

Figure 8 is an enlarged fragmentary side elevational view, with parts invertical section on the line V'II--V'II of Figure 10, in the directionof the arrows, of the table in diagonal or tilted position, in theprocess of being moved between the position of Figure 1 and that ofFigure 2.

Figure 9 is an enlarged fragmentary side elevational view, with parts invertical section on the line VII-VII of Figure 10, in the direction ofthe arrows, of the table in the position of Figure 2.

Figure 10 is an enlarged fragmentary vertical sectional view, on theline XX of Figure 9 in the direction of the arrows, parts being shown inelevation.

Figure 11 is an enlarged fragmentary side elevational view, with partsin vertical section on the line VII-VII of Figure 10, of the tablepositioned as in Figure 3.

Figure 12 is a fragmentary side elevational view, with parts in axialsection, of the screen counterbalancing spring assembly and X-ray tubeadjusting arm.

Figure 13 is a set of transverse sectional views, the upper elements ofwhich illustrate the knob, pointer, and dial assembly in differentpositions viewed from the top of Figure 12, while the correspondingviews, immediately therebelow show, first, sections on the line A-A ofFigure 12, and then, sections on the line B-B of Figure 12, in order toillustrate what the various pointer adjustments mean as to the positionof the index rod and its relationship with the spring-confining plates.

Figure 14 is a fragmentary axial View, on the line XIV-XIV of Figure 12,in the direction of the arrows.

Figure 15 is a fragmentary axial sectional view, on the line XVXV ofFigure 12, in the direction of the arrows.

Figure 16 is a transverse vertical sectional view on the line XVI-XVI ofFigure 17 in the direction of the arrows, showing in elevation the crankfor moving the Bucky diaphragm.

Figure 17 is a longitudinal sectional view on the line XYIL-XV'II ofFigure 16, in the direction'of the arrows.

of the operating crank and the spring-releas'ling segment on its shaft.

Figure 22 is a perspective view'of the operating pinion and its lockingsegment.

Apparatus providing for both vertical and horizontal fluoroscopy aswellas vertical and horizontal radiography are not unknown in the X-ray art.However, it has heretofore been necessary to'either use two X-ray tubes,one for radiography and the other for fluoroscopy, or use one X-ray tubeso'mounted-so 'thatit can be moved from a position above the X-ray tablefor'radiography, to'ajpositionbeneath said table for fluoroscopy.

The X-ray table of the present invention uses only one X-rayztube forboth radiography and fluoroscopy, and differs from previous designs inthat it tilts from ahorizontal position, such as shown in Figure :1,through a vertical position, suchas :shown'in Figure '2, to the reversehorizontal position, shown in Figure 3, rotating a total of 180. Thisfeature of tilting 180 makes it unnecessary to shift the X-ray tube fromabove the table to beneath the table, while switching fromra'diographyto-fluoroscopy, as in our X-ray table both the "initially top surface,and that which is then the bottom surface of the table, areused -asoperatinga-reas.

Considering a preferred embodiment of our invention, in a general way itincludes, a three- .positionhand-rock tilt table 21-, desirably about45- long by 28" wide and not more than thick, the frame of which isconstructedof steel of sufiieient section-to insure rigidity Whenin ahorizontal position and carrying a 200 pound patient. The table I isprovided with rails 10 within the body thereof to slidablyguide shoes 90car-ried-by the housing of a Bucky diaphragm 22 .-for=adjustabl-ysupporting the latter. The Bucky '22 holds'the cassette and itsphotographic film, and when installed, faces the side of the table, 2 l

at which the X-ray tube 23 is mounted, said 7 Bucky not beingcounterweighted. The table bod-y desirably'containsfixed lead or steelcounterweights 24, so that tilting it will require a pull not greaterthan-30 pounds, it being noted that the'pivot axis 25 for the table isnot equidistant from the ends of the latter. 7 V

Inside the table is a longitudinally-movable carriage 26, desirablycounterweighted as indi cated at H0, connected thereto by steel balls2'1 between its edges and corresponding tracks near the sides-of thetable.- Mounted on said longitudinally-movable carriage, is atransverselymovable carriage 28 which may include a shutter (not shown).It is correspondingly mounted for free movement in tracks attachedtosaid'longi- 4, 35 received in spherical bushings 36 and 37, ad justablycarried in bearings 38 and 39 in the legs 32 and 33, respectively. Thebolt 34 passes outwardly from the inner sideof the table side wall 4|,:through reinforcing plate 42, bolted to said side wall, and block43"Welded to"said plate, :through latch 29 and bushing 33. It has itsend received in nut means 44. The pocket receiving the nut means, whichmay involve two nuts for locking purposes, is desirably closed by a cap45.

The'bearing 38 fishld in place in leg 32, by plate so sec-uredbylscrews.

Thetother pivot bolt 35 passes from the outside into leg.po'cket, whichis finally closed by cap 20, through bushing 31, retainer plate 46 heldto leg "33 "by'screws'fl, washer 48, and the reinforcing plate 149desirably welded to side wall 5| of table 2|.

The latch 29 is controlled by release .knob 54, through conneotingarod.55 whichjis normally urged into locking positionbyrneans of coilcompression spring 56 thereon, acting between a collarfil fixed o-ntherod and a stop and guide 58 mounted on the inner surface of the sidewall M of the table 21. The otherend portion of the rod moves ina guide59. TheQIa tch 2.9.has a slot 6| through which the bolt '34jand a guidelug 40 on the stop block 43 passes, while helding'uiding relationtherewith by plateifl securedto 'saidlug by screws 6'0, allowingmovementby the release knob 54 from latched'position, shown in Figure 7,r

to unlatched position shown in Figure '8, where the prong 620i the'latch2 9 has'been withdrawn from the shoulder '63 on theleg '32. Thispermitsthe table tobe'tilt'ed or moved clockwise or in the direction ofthearrow 64 only, counterclockwise rotation being prevented'bytheengagement between the stop block rib m and the shoulder 63 of theleg 32 on the one side,.and the adjusted stop screw .53 andth'e abutmentportion I44 on the leg vit's-on the other, to theposition representedinii ligur Bfrom whence it is free to be returned or moved to theposition represented in Figure 9 where, if the knob 54 released,thelatch will drop to the locking position there represented, whereitsprongs'6'2 and'fii straddle the shoulder or lug lifi on the leg 32, tothereby hold the table lockedvin vertical position.

Upon again. releasing the-knob '54, by, pulling in the direction offthearrow 67, the latchi29 is Withdrawn from the lug 66, allowingthe tableto be tilted further .until finally the position represented .in Figure1-1 is reached where further movement is prevented 'by engagementbetween the rib and'the shoulder 168, on the .one side, and the adjustedstopscrew I45 and the abutment portion 1 34 on the other, andthelatchLZQ'haS snapped over said shou1deri'68,.with itsprong 6'5positioned in locking engagement therewith.

This preventsreturnmovement of the table2l until the index latch isagain released'lby .cor-

V responding movement of the control k'nob' 54.

tudinally movable carriage. The longitudinal movement is desirably about2'7 and the transverse movement desirably-about 8''.

A latch 29, shown in detail'in Figures 7 to '11, inclusive, slidable onguide and stop block 43, is

provided for holding the table 2| in adjusted position with respect tothe base 3|, which'inlthe present embodiment is formed by legs 32 and33.

The table is pivoted to said legs by bolts '34 and Referring nowto'thecrossharriage screen arm and tube arm assembly, illustrated inFigures 12 to 15, inclusive, there is. shown the details of themechanism which adjustably carries the X-ray .tube 23 andfiuorescentscrenili l. This assembly, represented generally by thereferenc character .15, .comprisesa hollow metal cylinder or tube 72,

preferably formed. of steel, and mounted on the transversely-movablecarriage 28,.so as to stand vertical when the table is horizontal, as.in the positionof Figures'l, 3, 5, and 6, andhorizontal when the tableis vertical, as in the .position of Figures 2 and 4.

Inside of the cylinder I2 is a compression spring I3, confined betweenplate I4, which may consist of two pieces secured together, and plateI5, the latter of which rests on a spacer tube I6 held in place incylinder I2 by screws 11, and with its outer end closed by a cover plate18. The latter is secured to a spring adjusting plate I9, by bolt 8|,the outer end of which is finally covered by nut I43. Plates I4 and I5appear respectively as upper and lower members of the spring adjustingassembly in Figure 12, which corresponds with the table position ofFigures 3 and 5 for horizontal fiuoroscopy, but the assembly is ofcourse reversed when the table is turned over for horizontalradiography, as in Figures 1 and 6.

The spring I3 is held under the desired compression by being urgedagainst the plate I5 by the adjusting rods 82 and 83 threaded into theplate I4 to the desired extent, as illustrated in Figure 15, andcarrying threaded ends to which nuts 84 and 85 are applied, after theyare passed through apertures in plate I9. The bolt 8| has a head whichmay serve as a limit stop against downward movement of the index rod 89,which controls the operation of the screen supporting arm 81 inaccordance with the angular position thereof, determined by the locationof the pointer 88 on the control knob 89. The latter is non-rotatablysecured to the upper end of the rod 86, as by means of pin 9|, andmovable with the rod and pointer over dial 92 for positioning in any oneof three positions.

The rod 86 carries a pin 93, shown as upper in Figure 12, and a pin 94,shown as lower in said'figure, adapted to engage the adjacent plates I4and I5, respectively, or pass through slots 95 and 99 in the plate I4,9! in the plate I5, or move in safety guide 98 projecting from saidplate I5. The ends of the safety guide 98 project different distancesthrough the carrying plate I5, forming a long safety stud 80 to preventmore than 129 rotation of the rod 86, and a short safety stud I95 toprevent the pointer 88 and rod 89 from being turned from position #3 toposition #1 without first releasing said index rod from force of springI3.

The screen-arm-end of the tube I2 carries a cap 99, through a slot I90in which passes index rod 86. Bearing lugs IOI project from the cap 99,and between them is pivoted the screen arm 87, as by means of pivot pinI02. The extreme end of the screen arm 81 is pivoted to the index plateblock I93, rotatably mounted on the rod 86 and to which the dial 92 issecured. Engagement between the block I03 and cap 99 may be resilientlyprevented by spring I04, confined against the block I03, as by pin I46through rod 89 and washer M1; or non-resiliently by a collar mounted onrod 88 and locked in the desired position by a setscrew (not shown). Byvirtue of the described arrangement, the screen arm 81 mayalternatively; be released from the spring for free movement, inconnection with vertical fiuoroscopy, have its weight balanced by thespring, as for use in horizontal fiuoroscop or be locked for use inhorizontal radiography.

The screen 69 is freed from the action of the spring i3 by turning theknob 89 and its pointer 88 to position #1, represented in Figure 13 bythe views in the left column. In this position the index rod 88 willtravel freely along its axis, because its pin 94 slides in the safetyguide 98, and moves without opposition through slot 91 in plate I5,while the pin 93 likewise moves freely without opposition through slotin plate I4, rotation of the rod 93 being prevented during the entirerange of screen travel by saidsafety guide.

In order to change the action of the spring I3, from one where thescreen 69 is free thereof to one where it is balanced thereby, thescreen 69 is pulled away from the table 2 I, as from position shown indotted lines in Figure 5 to that in full lines thereof, causing theindex rod 86 to travel into cylinder I2 until, at the extreme end oftravel, index pin 94 is not only through plate I5 but clears the end ofsafety stud I05, whereupon the pointer 88 is turned to position #2 onthe dial 92, and the parts left in the position shown in the middleviews of Figure 13. Here the pin 94 is in engagement with the bottom orouter surface of plate I5. The index pin 93, however, is then betweenthe plates I4 and l5, but free to move through the slot 96 in the plateI4. This means that downward movement of the screen, as from the fullline position in Figure 5 to the dotted line position in said figure, isresiliently opposed or balanced by compression of the spring I3 againstthe plate I4, by movement of the plate I5 toward it by correspondingpressure of the pin 94 on the bottom of said plate I5 as the rod 88moves upwardly.

The locked position, where the screen is held off the floor when thetable 2| and parts carried thereby are reversed, as represented inFigure 6, is obtained by moving the pointer 88 to position #3 on thedial 92, where the positions of the pins 93 and 94 are represented inthe views in the right hand column of Figure 13. This position isentered from that of position #2, shown in the middle column of Figure13. The index pins 93 and 94 are so set in the rod 86 that when thescreen is pushed toward the table, passing its midpoint of travel, indexpin 93 just passes through plate I4. Then, turning the knob 89 so thatthe pointer 88 moves from position #2 to position #3 on dial, the spring13 is confined to a short length by the pin 93 engaging the top of theplate 14, and the pin 94 engaging the bottom of the plate I5, therebyplacing the spring under an extra amout of compression, and making itsuificiently rigid to hold the screen substantially horizontal above thetable, when in the position represented in Figure 3. When the table 2|is turned to the position represented in Figure 6, the screen is held ina substantially horizontal position and prevented from dropping on thefloor by force transmitted to block I03, through rod 89, pin 93, plateI4, bolts 82 and 83, from plate I8. Plate I8, in turn, receives thisforce through bolt 8|, and plate I9 to which said bolt is secured as bywelding, from spacer It, to which plate I9 is also secured as bywelding, and through securing screwsil to column I2.

The X-ray tube 23 is carried by arm I09, the outer end of which ispivoted to a member I01 which encircles the lower end, as in Figure 12,of the tube I2, and is adjusted by mechanism I09 consisting of a jackscrew III carrying a swivel nut II2, pivoted between arms H3 and H4 ontube arm I98, a thrust bearing H5 and a thrust collar I I9, betweenwhich are mounted a pivoting abutment device III, also pivoted in abracket II8 secured to the column I2. The outer end of the jack screwIII carries a crank and handle assembly II9, non-rotatably mountedthereon, as by means of a pin I2I. The other end portion of the jackscrew III carries locking limit nuts I22 and I23. on one side of thenut, H2. and

i'ockingjlimit nuts 1'41 and 448-011 the'otherside; while the extremeend carriesiawasher I 24 ,a:lock washer: I2 5, -and a screw I26 aholding them-in place; It will thus be seen that turning of'the handleI21 of the assembly I09 efiects raising or lowering of thearm-supported-tube 23-, depending" on the directionofiturningt Referringnow to Figures 16-to 22', inclusive,

there'is shown the mechanism for moving the Bucky diaphragm 22. To theend Wall I28 of said Bucky is secured a supportingand spring housingbracket I 29, providing bearing *I3I tor the crankshaft I32, and bearing133 "for pinion I34. The'pinion" I34 carries a locking segment I35;.while the'crank shaft I32 carries a releasing segment I36, both *ofwhich segments are, when assembled, encirclediby coil locking springI31, having radial end portions I25 and I30, housed in a portion I40 ofthe-support bracket I29, and slightly larger in free outside diameterthan that of thebore of the housing portion I40; radial'springportionsare disposed between the segments I35 and I36. A-force or torque on thepinion I35, in either direction of rotation, "will cause the lockingsegment I35 to engage one of said end portions and tend to turn thespring in a direction to increase its diameter. 'Since the spring isconfinedit'cannot expand, and because of the initial pressure on itsoutside surface, it resists turnin like a difierentialband brake workinginternally. This prevents the Bucky .from unintentionally moving one wayor the other, whereby it is locked with respect to a pinion-engaged rackI38. The lower surface of said rack is engaged by roller I39.

This lock against Bucky movement is released by turning the crank handleI4I on the end of shaft I32 in either direction, causing the crank shaftrelease segment I35' to engage one of the spring end portions I 28andl3ll and wind-up the spring, as represented most clearly in'Figure19, thereby slightly decreasing its diameter and releasing the pressure,only one coilat :a time, until the spring resisting-friction islsmallenough to' be readily overcome. It will be seen that, while theconnections could be reversed, in this embodiment the drive assembly isattached to the Bucky, and the rack 138 to the chassiseof the table, tobe engaged by the drive pinion I 34,

whereby the weight of the Bucky appears as torque exerted on the springlock. The roller I39 and associated washer I42- prevent disengagement ofthe rackand pinion.

From the foregoing, it will be seen that we have provided an X-ray tablewhich is not-only adj ustable for use in horizontal or verticalposition,

but-in which provision is made for the-ready handling of the X-ray tube,fluoroscopic screen, and Bucky, as wellas insuring that the table issecurely locked in the desired horizont'alflor vertical position.

Although preferred embodiments of our invention have been disclosed-itwill be understood-that modifications may be made within the spirit andscope of the appended-claims.

We claim;

1. In X-ray apparatus, a base a table pivoted on-saidbase and swingable180so asto lie horizontally, while exposing one side or the other, orstand in a vertical plane, thereby adapting it for horizontal orvertical fluoroscopy and.horizontal or vertical .radi'ography,iacarriage "movable longitudinally in tracks attached to the sides of saidtable, a second carriage movable transversely in tracks :attached tov:said longitudinally The.

amen

8 movablezearriaseva fluorescent rscreen', asupporting arm extending"from-said screen; a screen counter-balancing spring, assembly securedto said arm.- and :means supporting said screen,- arm and springassemblyifrom .said second carriage; 2. In 'X-ray-apparatus, legs withstop shoulders, a "table pivoted on said legs and swingable 180, so as"to 'lie horizontally while exposing. one side or the other, or standin'a' verticalplane, thereby adapting it for horizontal -.or verticalfluoroscopy 'and' horizontal :or vertical radiography, and

means for locking saidtable in-any one oflsaid three positions, saidmeans comprising a stop block secured to a sideof said table, having anabutment portion projecting outwardlyand swingable with said tablethrough between said stop shoulders, a latch slidable .onsaidrstopblock,an opera-ting .rod secured to? said latch, a collar on said rod,:a-control knob on the far' -end of said rod, guide meansbn.saidtableforsaid rod, alocking spring mounted on said :rodzandcompressed between one of the said guide means and said collar to biasthe latch toward locking position, said latch having projections one ofwhich engages one of said stop shoulders-when in one horizontal portion,and the other of which engages asecondof saidstopashoulderswhen intheother horizontalposition, while both straddle another of said stopshoulders when the table is in vertical position, whereby said table maybelocked in anyone of the threeidesired positions;

3. In X-ray apparatus, a base, ,a table pivoted on said baseand'swingable 180 so as to lie horizontally while exposing oneside-orthecther or stand in a vertical 'plane, support means on saidtable for an X-ray tube and an associatedfluorescent screen, "a screencounterbalancing assembly mounted on said support 'means and com!-prising a hollow column, a compression spring enclosed in said column,means confining and adjusting the compression or said spring; a rodmovable in said spring and carrying index pins, the'means confining saidspring being'slotted, one of said means carrying a guide for one" ofsaid pins, means pivotally mounting said arm intermediate its ends withrespect to said col:- umn, a collar rotatable on said rod, a-- kn,ob andpointer assembly secured to the endofsaid rod beyond said collar, meanspivotallyconnecting the extreme-end of said arm to said collar, saidknobserving to turn said rod-to adjust itsrelation with respect to saidslotted spring-confining means, whereby the screen maybe released-fromsaid spring and adapted to move freely for use in vertical fluoroscopy,balanced by said spring for use in horizontal fluoroscopy, or locked topreventit dropping on the floor when vthe-apparatus is used forhorizontal-radiography.

4. In X-ray apparatus, a base, a table ,pivoted on said base andswingable 180 so as to lie horizontally, while exposing one side .or theother, or stand in a vertical plane, thereby adaptingrit for horizontalor verticalfluoroscopy and horizontal or vertical radiography, acarriage movablelongitudinally in tracks attached to the sides-of saidtable, a second carriagemovable transversely in tracks attached -.tosaid longitudinally movable carriage, a .V-fluorescent screen, asupporting arm extending fromssaid screen, a screen counterbalancingspring assembly comprising a hollow cylindrical column mounted on saidtransversely. movable carriage, a compression-spring enclosed insaidcolumn, meansv confining and adjusting, the compression of -.saidspring, a rod movable :in said springand i9 carrying index pins, themeans confining said spring being slotted, one ofsaid means carryingaguide for one of said. pins, means pivotally mountingsaid armintermediate its ends to said column, a collar rotatable on said rod, aknob and pointer assembly secured to the end of said rod beyondsaid'collar, the adjacent end of said arm being pivotally connected tosaid collar, and said knob serving for turning said rod to adjust itsrelation with respect to said compression spring,

whereby the screen may be; released from said. spring and adapted tomove freely for use in vertical fluoroscopy, by positioning said knob sothat one of said pins moves in its guide and the other passes freelythrough slots in the adjacent confining means; balanced by said springfor use in horizontal fluoroscopy, by positiong said knob so that one ofsaid pins engages one of said confining means while the other pin passesfreely through the other confining means; or locked to prevent itdropping on the floor when the apparatus is used for horizontalradiography, by positioning said knob 50 that each pin engages the outersurface of the adjacent confining means.

5. In X-ray apparatus, a support, a fluorescent screen, a supporting armextending from said screen, a screen counterbalancing spring assemblycomprising a hollow cylindrical column mounted on said support, acompression spring enclosed in said column, a rod movable in said springand carrying index pins, plates engaging the respective ends of saidspring for confining the same, means acting on one of said plates foradjusting the compression of said spring, both of said plates beingslotted and one carrying a guide for one of said pins, means pivotallymounting said arm intermediate its ends on said column, a collarrotatable on said rod, a knob and pointer assembly secured to the end ofsaid rod beyond said collar, the adjacent end of said arm beingpivotally connected to said collar and said knob serving for turningsaid rod to adjust its relation with respect to said spring, wherebysaid screen may be; released from said spring and adapted to move freelyfor use in vertical fluoroscopy, by positioning said knob so that one ofsaid pins moves in said guide and the other passes freely through slotsin the other plate; balanced by said spring for use in horizontalfluoroscopy, by positioning said knob so that one of said pins engagesthe plate which is not acted on by said adjusting means while the otherpin passes freely through slots in the other plate; or locked to preventit from dropping on the floor when the apparatus is used for horizontalradiography, by positioning said knob so that one of said pins engagesthe plate, which is not acted on by said adjusting means, on its outersurface, while the other engages the other plate, also on its outersurface, without making use of any of said slots.

6. In X-ray apparatus, support means, an X- ray tube mounted on saidsupport means, and adjustment means for said tube comprising an arm oneend of which is secured to said tube and the other end of which ispivoted to said support means, said arm having means in which a nut isswiveled, a jack screw threaded through said nut, means holding againstlongitudinal movement while allowing turning of another portion of saidjack screw with respect to said support, and means for turning saidscrew to adjust the angularity of said arm with respect to said support.

'7.- In X-ray apparatus, a base, a-table pivoted on said base andswingable soas to lie horizontally while exposing one side or the otheror stand in a vertical plane, support means mounted on said table, anX-ray tube mounted on said support means, and adjustment means for saidtube comprising an arm one end of which is'secured to said tube and theother end of which is pivoted to said support means, said arm havinglateralprojections between which is swiveled a nut, a jack screwthreaded through said nut, means pivotally holding'another portion ofsaid jack screw with respect to said support, and a. crank for turningsaid screw to, adjust theffangularity of said arm with respect to saidsupport.

8. In X-ray apparatus, a table, a Bucky diaphragm mounted to movelongitudinally in said table, a bracket, a crank with a shaft mounted insaid bracket, said shaft having an unlocking segment, a pinion pivotedon said shaft and carrying a locking segment, a coil spring encirclingand with radial end portions disposed between said segments andfrictionally housed in said bracket, a rack engaged by said pinion, oneof said bracket and rack being mounted on the Bucky and the other onsaid table, and a roller engaging said rack to insure meshing of it withsaid pinion, whereby turning of said crank in either direction acts onone of said end portions, releases said spring, and allows correspondingmovement of the Bucky, while said Bucky is locked against unintentionalmovement by the spring binding in its housing and made tighter byengagement of the locking segment with an end portion thereof.

9. In X-ray apparatus, a base, a table on said base, a Bucky diaphragmmounted to move longitudinally in said table, and means forsimultaneously preventing undesired movement of said Bucky, whileallowing for desired longitudinal adjustment thereof, comprising abracket secured to one end of said Bucky, a crank with a shaft mountedin said bracket, said shaft having an unlocking segment, a pinionpivoted on said shaft and carrying a locking segment, a coil springencircling, and with radial end portions disposed between, said segmentsand frictionally housed in said bracket, and a rack mounted on saidtable and engaged by said pinion, whereby turning of said crank ineither direction acts on one of said end portions, releases said spring,and allows corresponding movement of the Bucky, while said Bucky islocked against unintentional movement by the spring binding in itshousing and made tighter if a locking segment presses on an end portionthereof.

10. In X-ray apparatus, a base, a table pivoted on said base andswingable 180 so as to lie horizontally one way or the other or stand ina vertical plane, a Bucky diaphragm mounted to move longitudinally insaid table, and means for simultaneously preventing undesired movementof said Bucky, while allowing for undesired longitudinal adjustmentthereof, comprising a bracket secured to one end of said Bucky, a crankwith a shaft mounted in said bracket, said shaft having an unlockingsegment, a pinion pivoted on said shaft and carrying a locking segment,a coil spring encircling, and with radial end portions disposed between,said segments and frictionally housed in said bracket, a rack mounted onsaid table and engaged by said pinion, and a roller engaging said rackto insure meshing of it with said pinion, whereby turning of said crankin either direction acts on one of

